US2002614A - Process and apparatus for compressing coal in a chamber oven; retorts and the like - Google Patents

Description

May 28, 1935. H. PE'rscH 2,002,614

Pnocmss `AND APPARATUS FOR coMPREssING coAL IN A CHAMBER OVEN; RETORTS AND THE LIKE4 Z'Sheets-Sheet l Filed Sept( 18. 1931 H. PETscH A 2,002,614 P ESS AND APPARATUS FOR COMPRESSING COAL A CHAMBER OVEN', RET S AND THE LIKE Filed Sept. 1951 2 Sheets-Sheet 2 May 28, 1935.

s Patented May28, 1935 n A.

- PROCESS AND APPARATUS FOR'COMPRSS- ING COAL IN A CHAMBER OVEN; RETORTS AND THE Hermann Petsch, Recklinghausen, Germany, as-

signor to the Firm CarlA Still, Recklinghausen,

Germany Application September 18, 1931, Serial No. 563,648

` InGermany September Z3, 1930 8 Claims. (Cl. 2025-36)l The invention consists in a process'and apparatus Lfor mechanically compressing, to any required extent, coal charged loosely into chamberv ovens, cake-forming boxes or `other rigid receptacles.'` e

The accompanying drawings represent devices and `rxieans for carrying out the process.

Fig. 1 represents, as an example ofthe application of the process toa horizontal chamber oven for the production of gas and coal, a vertical section of an oven chamber of this type, including also the hoppers projecting downwards from a charging car adapted to ,travel over the oven, the upper portion of the figure being an elevation of the charging box and gearing used in carrying out the process. "Fig. 2 shows diagrammatically one of thecompressing screws 23. lFig. 3 is Va detailed view of the beam carrying the compressing elements and shows the manner in which it is supported by and driven along the vertical frame members, in a modiedform of the invention;

Fig. 4 is a detailed view of one of the compressing screws; l a l Fig 5 is aview on line V-V of Figure 4.

rIfhe reference I representsthewovenchamber which'is closed on both sides bythe doors 2, is bounded abovel by `the oven roof 4V and contains the charge3 of loosely inserted coal. Six charging openings 5 and the usual lgas withdrawal opening 6, on which anascension pipe isplaced, are provided in the oven roof 4.j A coal charging car 33"of any well known construction, but with the additional equipment to be herein described, travels on rails over the ovenrooi`4. The charging car`33 is provided with a coal' bunker 1 disp charging in commonintosix downwardly pro-l jecting compartments 8 acting as hoppers. The discharge openings 9 of the hoppers 8 are so spaced as to permit them to be positioned di-` rectly over thecharging openings 5 in the oven roof. 5

A framing, connectedto the box 1, comprises two vertical guides I0 connected by an upper horizontal transverse member II and 'serves for guiding in its vertical movement`a horizontal girder I2. The latter is guided lat the vertical parts III of the framing by rollers I3, of which at least one on each side may be formed as toothed wheels and engage in corresponding `racks. arranged at the guides I0 as shown in Fig. 3. lIwo cables I4, connected to the girder `I2 and led over guide rollers I5 secured to the transverse member II, serve, by means of a winding gear 29 driven by a variable speed motor wheel 22 which meshes with a gear 2l keyed to pressingtool 23.

30, to raise and lower the girder. The girder I2 may also beraised and lowered by means of the arrangement shown in. Figure 3 in which, instead of cables, a variable speed motor 3| is carried by the girder and is connected bymeans of `a 'chain'and sprocket arrangement to drive the pinions I3. Adjustable counter-weights are at- Ajtached to the cables to partly balance the weight `f of the girder. If the toothed wheels and rack gearing are provided between theparts I3 and I0, they can serve by means of a variable speedmotor 3l or other suitable machine to impart a positive upward and downward movement to'the girder I2. Instead of the toothed'wheels and rack gearing a chain wheel with a driving chain can also be provided. Six vertical shafts I1 are suspended in bearings I6 from the girder I2 and a bevel gear wheel I8 `is connected to `the upper end of each shaft. This number of six is optional; a larger number would usually `be preferable. Other bevel gear wheels I9 serve to operate the vbevel gear wheels I8 and are disposed on a shaft 2i common to the whole girder and supported in bearing blocks 20; The `shaft 2l carries a gear the shaft of motor 28. v p

The shafts I1 project downwards through the hoppers 8 and the charging openings 5 in the oven Aroof into the oven chamber I and carry at their lower ends helically or spirally formed compressing members e. g. worms or screws 23 shownin detail in Figure 4 ,which act as the actual compressing tools. In the example shown in the drawings, the axallength of the worm is less than the depth of the)charge 3 of coal. The axial cross-section of 'the helical surface orthread of the worm is preferably triangular, the under side voijthe helical surface of the worm is inclined upwards from the axis and may also be curved, so as to vform a conical surface, of which thevertex is directed downwards. The external diameter of the worm is preferably reduced at both ends, viz; is greatest at the central portion. It may also be cylindrical whereas the shaft of the worm is conically enlarged towards its end. Instead of the turn of the Ascrew a spiral of Archimedes vor a multiple thread screw may be used. Close to the ,position in which a worm 23 is connected to the -shaft'll there is a stirring blade 24 (Figures 4 and 5), the greatest radial extension of which is greater than the largest radius of the comi The blade 24 may extend to a distance greater than the radius of the charging opening 5. `In this case it is necessary, in other cases it is advisable, to construct the blades so 55 that, during their passage through the charging openings 5 and the discharge openings 8, viz. during the introduction and withdrawal of the worms 2l, they are hinged so as to lie closely against the shafts I1.

The suspension of the shafts I'I at their upper ends in the bearings I6 and their gearing are preferably arranged so that the shafts II and with them the worms or spirals 23 are shaken during their vertical movements. This can, for example, be effected by the arrangement in whicheach supporting ring of the bearings I6 has a waved or sinuous contour instead of a plane surface, and these surfaces from the races of ball bearings. Care must naturally be taken that these vertical impulses are not imparted to the bevel gear wheels I8, or that by suitable constructions they do not injuriously affect the operating gearing. 1

The described arrangement is operated as follows:

The girder I2 with it all the worms 23 is raised into its highest position in which the worms are outside the oven chamber I, or the girder is lowered until the worms are just below the charging openings 5, and coal is looselyinserted in the usual manner from the box 'I of the charging car through the hoppers 8 and the openings 5 into the oven chamber I, forming projecting conical piles 25 of loose coal on the charge 3. In this condition, parts of the coal charge extend into the openings 5 and even into the hoppers 8, as

shown in Fig. l.

The girder I2 with all the .worms and worm shafts connected to it is guided vertically downwardsand the shafts I'I are set in rotation by the motor 28 operating the gearing 22. If, as shown in the drawings, the threadsof the screws 23 are right-handed, during this working stage a right- .handed rotation, as seen from above, is employed.

The worms are simply screwed like corkscrews into the charge 3, since their weight is counterbalanced, they are unaiected byA frictional resistance and descend freely, that is, without any mechanical pressure. In order, according to the invention, to compress the coal in the'chamber,

.care must be taken that simultaneously with the downwards movement of the worms, the charge must be displaced not only both downwards in the direction of the axes of the worms, but also laterally outwards, that is radially from the axes of the worms. This can be effected simply by the arrangement in which the worms are pressed downwards by a denite portion of their own weight and that of the supportingy girder. The effective portion of this weight can, for example, be adjusted by the amount of balancing weight applied to the cables I4. Since the under side of thev helical thread -of each worm 23, as above mentioned, is inclined conically upwards, when a .pressure is exerted on the worm from above, not only a downward component, but also a lateral component, of the pressure is exerted within the charge of coal. By their rotational movement and the simultaneously downward pressure, the worms are drawn from their highest position to the bottom of the oven chamber I.

When this condition is attained, the gear operating the rotational movement of the worms and the simultaneously downward movement of -the girder I2, if it is in action, is stopped and the direction of rotation is reversed, that is, the right-handed screw threads 23 are now rotatedA to the left and screw themselves upwardly out of the charge. If during this upward movement, the worms are pressed down, for example by the weight of the parts, the coal is compressed dur-4 ing this path in the same direction as previously duringthe downward path of the worms.

It is advisable to arrange so that the amount of the effective weight is different in the upward and downward paths of the compressing tools.

Instead of using the action of the weights, the worms can be pressed downwards mechanically. In this case, the worms are rotated and an up- Lward and downward motion also imparted to the girder I2 by suitable gearing, the ratio of gearing between their movements being adjustable, or by the positive action of the variable speed motor drive of Figure 3. A movement is effected, which applies also to the previously described case in which the worms are loaded by the weights, as shown diagrammatically in Fig. 2. A point A on the periphery of the helical surface of the screw-thread, if there were only a rotational movement of the worm, as in the case in which the worm is entirely relieved of the weights, would in descending traverse the path A-B, on ascending the path A-C. Il' sutlicient movement in the axial direction is imparted to the worm simultaneously with the movement of rotation, there is an axial acceleration, that is worm moving downwards during one rotation isto a distance greater than the pitch of the thread, the point A moving in the path A-D; and, if there is a retardation in the upward movement, the point A follows the path A-E.

Fig. 2 shows clearly that, in the process according to the invention, in both the downward and upward movements of the worm, the coal is displaced axially downwards. Also, obviously whatever may be the cross-sectional form of the worm thread, the coal is displaced laterally, that is radially outwards from the axes of the worms. This lateral displacement of the coal is assisted if the under side of the worm thread is inclined upwards, so as 4to form arconical surface. By suitably selecting the inclination, the components displacing the coal downwards and laterally can be varied to a certain extent.

If the worms, as'in the example illustrated, have an axial length corresponding to a fraction of the height of the charge of coal, they traverse in their upward and downward movements in succession different layers of the charge which are, therefore, continuously compressed or prepared for compression. In order to ensure the continuance ofA this action during the further movement of the worms, there must be a subsequent displacement of the coal in the direction from above downwards. If, as shown in the drawings, the upper. surface of the coal forms loose conical piles, andthe coal Aextends through the charging openings 5 into the hoppers 8, fresh coal slides down automatically into the charge as the worms press the mass downwards. This downward sliding action can be increased by the stirrer blade 24. This blade stirs the coal always at the places where it is favourable to form cavities directly above the screws 23, and, consequently, ensures, even in this case, that fresh coal is constantly shaken down.

When the worms are forcibly raised and lowered it is advantageous to impart a shorter acceleration and retardation inthe lower positions of the worms than in the higher, that is to vary the acceleration or retardation during the vertical path. By suitable constructions, such as ratio changing gears or the variable speed motor 28, this can be effected when the worms are acted on by the weight. 'Ihis method of work- -mass of coal in said oven in substantially the ing compensates for the decreasing or variable compression of the charge of coal from below upwards, which would occur without such measures.

When several worms are operating at the same time care should be taken that the fresh coal is uniformly supplied to all the worms. In the arrangement shown in the drawings this is effected,

for example,` by distributing devices applied between the coal containerv 1 and each of the hcp- "pers 8, which ensure a uniform supply of "fresh coal to the individual hoppers 8; such devices v may be slides which are always opened by a coupled gearing to the same'extent.

By the above-described devices, which may also produce the impulses imparted to the worms 23 or the shafts I1 the compressive action exerted directly by the worms `can be strengthened. 'Ihe vibrations imparted to the worms are transmitted to the surrounding charge of coal and cause it to be packed. The vibrations imparted to the worms can be exerted, not only as described above, in the axial direction, but also laterally.`

In this case, the upward and downward movements of the worms through the mass of coal can be repeated several times. By this, and similarly by varying the amount of the acceleration or retardation of the worms or of the pressure exerted downwards in the axial direction, the coal can be more and more compressedluntil the required degree of compression is attained.

The method of working can be modified as followst- The compression can be commenced when the worms 23 are in their lowest position on the sole of the oven chamber I, the coal being gradually charged through openings 5, while the worms 23 are screwed upwards and according to the invention under retardation at that time. In this way fresh coal is constantly charged to the places, at the upper end or the upper part of the worms, from which the coal is continuously removed and forced downwards to be compressed. Also, in this method of operation, in which the compression can be completed by a single upward movement of the worms, fresh coal is preferably charged through the different hoppers 8 to all the worms 23 uniformly, according the slope of the oven chamber l.

It is not absolutely necessary that the lengt of the worms 23 should be less than the height of the mass of coal to be compressed, or the path traversed by the worms in compressing the coal. It is possible to useworms extending over the whole vertical dimension of the charge of coal.

'I'he invention is also not restricted to using the worms in the vertical position. By the provision of suitable arrangements for supplying fresh coal in the space available for the reception and compression of the coal, under certain circumstances the worms may have positions other than vertical, for example horizontal or inclined.

What I claim is:-

1. In apparatus for compressing coal charged loosely into a chamber oven having a roof and spaced charging openings therein, comprising means carrying a plurality of spaced spirally formed compressing elements in registration with said charging openings and adapted to be simultaneously introduced through said openings 1n said roof and into contact with said coal, means for simultaneously rotating said elements and means for moving said elements into and out of a `same horizontal plane.

` 2. In apparatus for compressing coal charged loosely into a chamber oven having a roof and spaced charging openings therein, comprising a frame disposed over said roof, a cross girder movable vertically into said frame, a plurality of spaced spirally formed compressing elements suspended from said cross girder in registration with said charging openings'and adapted to be simultaneously introduced through said openings in said roof and into contact with said coal, and means disposed on said girder for simultaneously rotating said elements in common into and out 'of the charge of coal in said oven, and means for raising and lowering said girder.

3. In apparatus for compressing coal charged loosely into a chamber oven having a roof and spaced charging openings therein, comprising a charging car adapted to travel over said roof, a frame attached to said car, a cross girder movable vertically in said frame, a plurality of spaced spirally formed compressing elements suspended from said cross girder and adapted to register with said charging openings and to be simultaneously introduced through said openings in said roof and into contact with said coal, means for simultaneously rotating said elements, and means for moving said elements into and out of said coal in substantially the same horizontal plane.

4. In apparatus for compressng coal charged loosely into a chamber oven having a roof and spaced charged openings therein, comprising a charging car adapted to move over said roof, a frame attached to said car, a cross girder, guides forming part of said frame for guiding said cross girder for vertical movement, a horizontal shaft carried by said girder, means for rotating said shaft, a plurality of spaced vertical shafts geared to said horizontal shaft for rotating at the same speed and suspended from said cross girder adapted to register with said charging openings and to be simultaneously introduced through said openings in said roof and into contact with said coal, a spirally formed compressing element fixed for rotation at the end of each vertical shaft, and means for raising and lowering said girder vertically to move said elements into and out of said coal in substantially the same horizontal plane.

5. In the process of carbonizing coal, the step of compressing a charge of coal forrcarbonization which consists in charging coal loosely into a chamber with rigid walls and bottom, simultaneously moving spirally formed compressing ele ments into the chamber and into contact with said coal at a plurality of spaced points and then rotating said elements in substantially the same horizontal plane to apply a compressive force to said coal which distributes pressure in both a vertical and substantially horizontal direction to obtain a uniform compression of the entire charge.

6. In the process ofcarbonizing coal, the step of compressing a charge of coal in a chamber with rigid walls and bottom which consists in simultaneously moving spirally formed compresstarded rate of speed to obtain a uniform compression of he entire charge in both a vertical andV substa `tially horizontal direction.

'7. In the process of carbonizing coal, the step of compressing a charge of coal for carbonization whic consists in charging coal loosely into a chamber with rigid walls and bottom, simultaneously moving spirally formed compressing ele-- ments downwardly into said chamber and into contact with said coal at a plurality of spaced points, continuously rotating said elements while lowering them in substantially the same horizontal plane with accelerating speed to obtain a uniform compression of the entire charge in both a vertical and substantially horizontal direction.

8. In the process of carbonizing coal, the step of compressing a charge of coal for carbonization which consists in charging coal loosely into a chamber with rigid walls and bottom, simultaneously moving spirally formed compressing' elements downwardly intothe'chamber and into contact with said coal'at a plurality of spaced points and in substantially the same horizontal plane, continuously rotating said elements while lowering them with accelerated speed and while vertically withdrawing them with gradually retarded speed to obtain a uniform compression of the entire charge in both a vertical and substantially horizontal direction.

' HERMANN PETSCH.

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